A huge lake roughly two thirds of the size of New York City has developed an luminous green coloring that looks out of this world.
What's more disturbing is the eerie green swirls that are apparent, and so intense that they can be seen from space, indicate something dangerous is taking place.
And multiple lakes are affected.
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In fact, Pyramid Lake, in northeast Nevada, is highly toxic due to a phenomenon that occurs almost every year.
NASA released photos of the black and green body of water last month, along with similar images of Clear Lake in California (from May) and Lake Erie (in August).
Thankfully, it isn't as alarming as you'd think at first and it has been happening for a heck of a long time.
Naturally, you'd imagine it came from some sort of sewage or chemical spill, but you'd be wrong, although it is still toxic.
It is just part of an algal bloom, and the only difference this year is that levels Nodularia spumigena - which is a type of cyanobacteria often found in warm, brackish or saline lakes - are a lot higher than usual.
It was identified by the Pyramid Lake Paiute Tribe that frequently check the algae levels in the lake - and they have now warned tourists to avoid taking a dip in the water... although I'm not sure who in their right mind would want to swim in a bright green lake.
Speaking to the San Francisco Chronicle, the Tribe said: "The bloom material is breaking down and is releasing the toxin microcystin into the water, which signals the turn towards normal conditions that may take 2-3 weeks to normalize."
Aaron Bill, a water quality manager with the tribe's natural resources department, has reiterated the sentiment.
He said: "We always want to make sure to make people aware of that, so that they would either not bring their animals out or they would restrict them and have their own safe drinking water."
Yes, the water is quite dangerous - in fact it has caused visitors to break out in rashes, have diarrhea and be fatigued.
But that's not all. When the toxin is inhaled it can even attack your brain.
When the San Francisco Estuary conducted examinations it found that chlorophyll-a and cyanobacteria b increase at the end of September till around the middle of October.
So if you're visiting Pyramid Lake at any point soon, be sure to stay away from the water.
Topics: Environment, Nature, Science, Health, Travel
Joe Yates